Rapid Antimicrobial Susceptibility Assay Using Flow Cytometry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for determining antimicrobial susceptibility in urine samples from patients with urinary tract infections (UTIs) are slow and inefficient, often requiring extended periods to identify effective antibiotics, contributing to antimicrobial resistance due to misprescription and overuse.
Innovation Solution
A rapid method involving contacting urine samples with growth media, incubating them with and without antimicrobial agents, and using flow cytometry to assess biochemical and biophysical parameters within 30 minutes to determine susceptibility, allowing for quick identification of effective antibiotics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional culture-based methods are used to determine antimicrobial susceptibility, then accurate phenotypic assessment can be achieved, but the testing time is extended to days
Solution Approach 1:
The patent applies preliminary action by pre-coating microtiter plate wells with growth medium and preparing standardized bacterial suspensions before actual testing. This allows the assay to begin immediately when samples arrive, eliminating preparation time and enabling susceptibility results within hours rather than days
Solution Approach 2:
The patent replaces traditional mechanical culture-based assessment with automated optical detection systems. Microtiter plates with optical detectors automatically measure bacterial growth in real-time, substituting manual daily colony counting with continuous automated monitoring that provides results much faster while maintaining phenotypic accuracy
2Productivity
If rapid testing methods are implemented to reduce prescription time, then antimicrobial resistance can be reduced, but the complexity of the testing system increases
Solution Approach 1:
The patent applies universality by designing a microtiter plate-based system that can test multiple antibiotics simultaneously against multiple bacterial isolates. The same platform handles sample preparation, antibiotic exposure, growth monitoring, and data analysis, reducing overall system complexity while enabling rapid comprehensive susceptibility profiling
Solution Approach 2:
The patent uses parameter changes by optimizing growth medium composition, antibiotic concentrations, and incubation conditions to achieve rapid bacterial growth and susceptibility determination within hours. Standardized parameters for bacterial suspension density, medium volume, and optical detection settings simplify the system while enabling rapid results
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables rapid identification of antimicrobial susceptibility in under 30 minutes, facilitating timely and appropriate antibiotic prescription, thereby reducing the risk of antimicrobial resistance and improving treatment outcomes for UTIs.
Implementation Method 1
passing the first and second mixture, or portion thereof, through a flow cytometer in order to assess one or more biochemical and/or biophysical parameters of the microorganisms in both mixtures
Implementation Method 2
The one or more biochemical and/or biophysical parameters of the microorganisms may be selected from one or more of the following: cell size, cell number, cell membrane energisation and/or nucleic acid content and/or distribution. The one or more biochemical and/or biophysical parameters of the microorganisms may be determined by assessing the uptake of one or more certain fluorescent or other stains.
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
The invention relates to a method for rapidly determining the susceptibility of a microorganism to an antimicrobial agent comprising the steps: a) contacting a first sample containing the microorganism with a first growth medium so as to form a first mixture, wherein the first growth medium is selected to enable the microorganism to proliferate and/or encourage the microorganism cell cycle to commence proliferation; b) contacting a second sample containing the microorganism with a second growth medium so as to form a second mixture, wherein the second growth medium is substantially the same as the first growth medium but further comprises a first antimicrobial agent which may inhibit or slow the proliferation of the microorganism; c) incubating the first and second mixtures, for 30 minutes or less, under conditions suitable to enable or encourage proliferation of the microorganism; d) passing the first and second mixture, or portion thereof, through a flow cytometer in order to assess one or more biochemical and/or biophysical parameters of the microorganisms in both mixtures; and e) comparing the parameters of the microorganisms in the first mixture with that of the second mixture, after incubation, in order to detect whether the first antimicrobial agent inhibits or slows the proliferation of the microorganism so as to determine the susceptibility of a microorganism to said agent. The method is particularly suited for identifying the which antimicrobial agents would be suitable for the treatment of microbial infections, such as Urinary Tract Infections (UTIs). In the corresponding kit an enriched growth medium, one or more antimicrobial agents and a carbocyanine dye are present.